Now kids, play nice


-Jamie
(aka Jack_of_Trades)

 

off topic-ish, but how the heck are you guys getting 260+ to the tank...
I cruise control at 70mph on the highway 95% of the time and at most i get 255.

Just yesterday I drove 125 miles straight @ 70 all the way, then did like few miles locally and cruise back home at 70 again and I only managed to get 258.5miles...

Should I go 60mph? lmao

 

The best mileage obtained I've seen is around 55mph. Also environment can effect the car's fuel efficiency. Elevation, heat, humidity. Lastly, most states have 92 / 93 octane, think all So-Cal has is 91? You'll get slightly better mileage from higher octane.

 

Actually, we generally get better mileage with 91 octane while cruising. 91 octane has easier combustion than 93 octane and the ignition timing is set to optimize 91 octane fuel.

-Jamie
(aka Jack_of_Trades)

 

But isn't that on a custom tune? Or is the factory one that way?

I know it's apples and oranges, but in my wife's OZ and my truck, I get better mileage using 92 vs 87.

 

Your only going to get really good mpg if you tune your car and ask them to tune for it. Other wise you will make more whp and they tune. It has a lot to do with your AFR. Personally I would rather a higher WHP/Tq

 

Stock USDM evo's are tuned for 91 octane since that's the highest "premium" fuel offered in ALL 50 states. The higher the octane, the harder it is to ignite. The only way your car should ever get better gas mileage by using a higher octane fuel is if your engine is experiencing engine knock, causing the ignition timing to be retarded. Which in turn, lowers your power output.

Ideally, you want to run the lowest octane fuel you possibly can without the onset of engine knock. This helps guarantee all of the fuel will ignite and yield the most power potential.

A main reason that cars can have poor gas mileage is from something forcing the computer to not run in closed loop in the cruising area, like it should. This will greatly affect gas mileage.

 

I get 7mpg in my semi so I think u should definitely take it to the shop to get it looked at. I have a gsR and I get at least 17mpg

 

well my car now has 3900 miles and my check engine light just came on i took it to the dealer and the spark plugs are melted at the electrode and the piece of metal that is gapped is gone........i think i need to dump this car sorry guys but to me it a pos .........

 

What size tank is in the 2011?

 

manual says: 14.5gal / 55 liter.

I agree 100% with what you have replied with, however I think the post about octane vs fuel economy was misunderstood. SoCal and AZ have E10/91+10%ethanol. The increase in the amount of ethanol requires more fuel to hit stoichiometric mixtures, so the fuel trims on our crappy fuel here causes us to burn a little more of it and causing a slight drop in our economy.


EDIT:
I have noticed every 3-5 seconds at WOT pulling on to the freeway takes about 10miles off the range of the tank (no tune or mods yet btw)



As I read this more and I see you filed a case with Mitsu, maybe more info can help for comparison. Sorry to see this has gone so bad, but the damage the car has is from a fueling problem. Sounds like you just need to go to a different dealership to start.

I have a 2011 WW Evo GSR
Phx, Arizona
Avg daytime temp is around 98-108 degrees
I'm filling on Chevron or Shell 91 Oct (10% ethanol)
Avg humidity has been less than 30% (about 15% more often than not)
I have just over 1k miles on the car in the past two weeks or so.



Vehicle,"Date/Time","Odometer Reading","Distance Unit","Volume","Volume Unit","Price per Unit","Total", "Partial Fill", "Skipped Fill", "Brand", "Type of Fuel"
Evo,"09/26/2011 -0 12:08","934","mi","11.734","gal","$3.729","$43.76" ,"No","No","0.0","MPG","Circle K","Gasoline -0 Premium
Evo,"09/23/2011 -0 05:27","701","mi","11.491","gal","$3.659","$42.05" ,"No","No","19.857","MPG","chevron","Gasoline -0 Premium
Evo,"09/19/2011 -0 19:51","475","mi","11.61","gal","$3.619","$42.02", "No","No","19.668","MPG","Shell","Gasoline -0 Premium
Evo,"09/17/2011 -0 18:26","242","mi","10.816","gal","$3.759","$40.66" ,"No","No","20.069","MPG","Shell","Gasoline -0 Premium
Evo,"09/15/2011 -0 18:00","51","mi","0.0","gal","??","??","No","No"," ??","MPG","","Gasoline -0 Premium

 

Do what you gotta do, but out of the thousands of owners on this site, no one has had this specific issue you just listed. Perhaps you got a lemon, perhaps you got bad gas at one point. But to say is fail, they have a good track record of good performing parts. Things happen to all manufacturers.